I made an exact copy of the setup from this link:
https://medium.com/@rxseger/esp8266-fir ... 25f317c74f
For that I used a fresh sensor without PCB because the other one could have been damaged by experimenting a lot and soldering en desoldering and I had a spare one. At first I even soldered the first sensor the wrong way round on the PCB.
I used 3.3k and 1k for the resistors because I could only measure 4.7 volts on the 5 volt pin of the Wemos D1. The measured voltage with these resistors on + and - only was 1.1 volts. After connecting to pin 4-5, 0.89 volts remained. This is then connected to the A0 (ADC) pin of the Wemos D1. However, this value does not change when I place the sensor in full sun. It even seems that the value then drops from 0.01 to 0.02??? This can be seen even better on the ESPeasy readout on the Wemos D1 where the value drops from 302 to 295. Bizarre! I would expect the value to go up. On the other hand, if I keep my finger on the sensor, the value does drop. Even if I cover the sensor with my iPhone, the value decreases and as soon as I switch on the LED lamp, the value goes back up to 0.89 volts. So that seems like a kind of maximum value. I don't understand it anymore.
Below are the results inside the house and in full sunlight. No difference
